Redknapp wrote in his book, 'Always Managing: My Autobiography by Harry Redknapp', which is being serialised in the Daily Mail: "His biggest test will be to step out of the shadow of Cristiano Ronaldo with confidence. That won't be easy.

"Ronaldo is a huge star at Madrid and will probably want to take nine out of 10 free-kicks - at least. Gareth will have to assert himself and that will require a strong mind.

"He has to think 'I'm an £86million player' and act like it, taking responsibility, claiming the ball when he fancies his chances. And yet at the same time he cannot dwell on his fee and what it means too much because that would put him under immense pressure. It is a tricky balancing act. He will have to be ready for the matches when he goes it alone, has a shot, misses and Ronaldo starts throwing his arms up in the air.

"He cannot, at that point, go into his shell and become this timid little creature. But it is not natural for Gareth to behave in an assertive way. Don't get me wrong, he knows he is good. The fee is crazy, amazing money, but he wouldn't have fought so hard to get the deal done if he didn't fancy his chances of living up to expectations in Madrid.

"Yet, equally, Gareth is a quiet lad, who spends time with his girlfriend and family, and I'm not sure being in the same bracket as Ronaldo and Lionel Messi will suit him."